1928 steel lifeboat sailboat conversion and freeboard

Discussion in 'Sailboats' started by newindustar, Jul 18, 2010.

  1. newindustar
    Joined: Jul 2010
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    newindustar Junior Member

    Hi - this is my first post here. Years ago I completed a 7 ton 28 foot double ended cutter and sailed it half way round (no. and so. Pacific).

    Houses, wives, and kids later with a new desire to feel the pull of a tiller, I just acquired a 1928 22 foot galvanized steel double-ended lifeboat built by the Welin boat and Davit Company NY. They built Titanic's davits. It is made of light gauge riveted galvanized gauge plates and had wooden sheers, seats, floorboards and one station of rowing blocks. It has very graceful all rounded sections perhaps most similar to a Monomoy row-able lifeboat, very pretty actually. Rather looks like a big canoe. The hull appears sound. Someone had done a rather respectable cabin sloop conversion on it many years ago which I had to strip as it was completely rotted. It came with a long steel keel about 1 1/4 inch thick which bolts to the lifeboat keel and supposedly weighs 1500 lbs. The fairly flat bottom hull has only about 14" freeboard amidships with 22 at stern and 26 at bow judging from the old waterline paint. Bulwarks added about 2 inches to the steel height. This yielded a cabin height not really even sit-able for a 6 footer like me as the keel to sheer inside height amidships is only 32 inches or about 40 with a boxy cabin. The original plaque on the bow claims 20 person 204 cubic foot capacity but offers no displacement value.

    Currently it is nothing but the original open hull with rotted wooded sheer. When they converted it they stepped the mast about 9 feet back from the bow, sloop rigged. I am considering adding a watertight steel bulkhead and deck extending from the bow about 7 feet aft. It would form a vee-berth with a hatch but would be a watertight compartment as well. Aft of this bulkhead I am considering an open boat with a keel stepped mast and watertight seating either side and also a watertight stern bulkhead and compartment as well which might make it hard to reach a tiller possibly necessitating a wheel. It has an inboard Onan aircooled 2 cylinder with a long prop shaft tube. The engine sits about 7 feet forward of the stern. So between the main fore and aft bulkheads I would have about 7 feet of open boat under the boom which should be workable and even comfortable sailing. I may need some more keel support in the open area as well such as a center plate over the keel and small bulkheads for the seating along the sided..

    I am totally open to other approaches but not sure if this hull will ever suit a cabin..

    I have two main questions in any case.

    1. I feel I need to raise the freeboard for sailing (definitely if adding a cabin). I don't know how much to add and if it should be parallel to the last sheer or have a different sheerr curvature double cut into the new top-plate. The first conversion did not raise the freeboard but did have a cabin and decks. I feel they should have raised the sheer before they got started. A 22-23 foor Atkins Hearts Desire
    http://www.boat-links.com/Atkinco/Sail/HeartsDesireII.html
    has a least freeboard of 2 feet l 1/4 inches, much more comfortable I would think than my 14 inches. This boat was designed to row thus the lower freeboard likely. I am prepared to add an additional steel panel(s), riveted, gas-welded, brazed or stick welded to accomplish this.

    2. How much volume in air-tight compartments would be needed to make the craft unsinkable? I don't know the weight of the hull. Keel engine and rigging at least 2000 lbs, I don't think over 4000 with the hull but don't know how to figure this. I have the old waterline, I think the cabin was fairly heavy. My steel bulkheads and decks will be less I think.

    It came with a aluminum mast from a C-scow which looks the right section and length about right for a fairly modern aspect ratio for a sloop.
     
  2. newindustar
    Joined: Jul 2010
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    newindustar Junior Member

    Hmmm.. zero replies

    I seem to have one of the rare posts with zero replies. I could sit here and try to guess what great faux pas I may have committed but would rather hear it from the horses mouth, such being forum members. It seems an odd way to greet a new member. I don't think the topic(s) were that uninteresting or inappropriate. Please enlighten me!
     
  3. welder/fitter
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    welder/fitter Senior Member

    Sorry, buddy, I didn't see your post! Maybe, others didn't notice it either. Do you have photos that you could put up, so that we have images of what we are going to discuss?

    Off the top of my head, without having seen your boat, I would be concerned with the metal composition used in the late 1920s and the service life of same. As I worked in the shipyards for a number of years, I've had quite a bit of experience with old workboats. rivets are a concern, the "iron" used lacked in ductility. But, I'm not trying to kick holes in your dream, it just seems like quite a challenge. Have you cut through any of the hull? Many times, I've cut into steel where the surface seemed solid, only to have the metal between the outer surfaces explode in my face( If seanherron reads this, he's laughing right now - let go the "fkn" trigger!). This was on boats much younger than yours.

    Maybe, you could tell us about yourself/your own experience, where your strengths & weaknesses are in doing this project? It would help us in how we explain/suggest things. As well, there are a lot of books which will help with your consideration of determining weights, increasing freeboard, etc. . This site has a lot of resources, hang in & you'll have more than enough help. But, like I said, photos would be a huge help.

    Mike

    Don't think you're being avoided, I often miss new discussions, as do others. Have you tried to find old design or construction plans for these boats? Often, they can be found in the archives of various museums.
     
  4. Tad
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    Tad Boat Designer

    Give it some time....it's summer and we finally have some decent painting weather after a spring of rain and cold....

    Your questions are an interesting puzzle for the beginning yacht designer/NA. In days gone by this would be a legitimate job, I don't know why today's students think this sort of project is beneath them. They seem to be way too busy making 3D surface models of mythic monster mega yachts that no one will ever build.

    Yes, I agree the freeboard should be raised. But without knowing a bunch more and doing some calculations I would not advocate building a raised deck of steel. It would be irresponsible to do so. Thus I suggest you could hire a NA to sort weights and centers....or you can do the legwork yourself and question by question figure it out here....it will take time....

    Years ago there was a little book published in Britain, Converting Lifeboats or something....decades out of print....

    The raised deck should have a flatter sheer than the main sheer, make it a bit higher midships.

    Give us length, beam, depth midships and at the ends, measurements of the ballast keel. You could throw her in the water and measure flotation to get current weight?
     
  5. latestarter
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    latestarter Senior Member

    Regarding question 1, I do not have the knowledge to give you any useful comments.

    But on question 2 my thoughts, in theoretical terms, (not based on a practical example) are as follows.

    The density of fresh water is 62.4 lb/ft cubed. Seawater is 2.5 to 3.5 % denser.
    An air tight compartment will have buoyancy, in fresh water, of its volume in ft cubed x 62.4 giving you the answer in lbs.

    That is the easy bit. You need to decide what you mean by unsinkable.

    Just having the top foot of the cabin top above water level is of little value, other than it would be easier to salvage than on the sea bed.

    If you want the boat to float high enough for you to survive on, until rescuers arrive, you will need much more.

    Stability when swamped is also vital. Depending where you put the compartments may mean the boat capsizes and stays there or worse is not stable either way up and just rolls.

    You would need to work out the greatest possible all up weight including crew etc and then add a factor of safety to calculate the volume needed.

    Having the compartments high up would be more stable when swamped but having the extra steel to make them high up would be less stable in normal use.
     
  6. newindustar
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    newindustar Junior Member

    Thanks so much for the replies. I realize I threw out a lot of incomplete ideas and raised questions that had no easy answers. I will get in pictures worth many of my words asap which should help.

    Let me start by saying my family and I moved to Minnesota a couple of years ago. Of course we are in the land of lakes and I started yearning to sail again after my blue water days. My kids are 5,8, and 11 and I wanted them and my unsalted wife to experience sailing. I was on a very tight budget (100s, not 1000s) when I found this boat for free on Craig's list. I loved the lines and the character right away and had it hauled home and stripped out the rotted cabin.

    It likely came from a Great lakes ship of some sort as it was from up in northern Minnesota. The hull appears very sound, maybe it was never in saltwater. The hull seems to have survived being under sail but I can know how long or hard she was sailed.

    My concept is for a local river and lake sailer, weekend or 2 week holiday gunkholer, not open ocean although Lakes Superior could be a test. I have limited resources for the project and also desire a simple, light, trailerable boat. I can see a boat showing it's galvanized riveted hull with an open structure of cedar timbers, and a mast. Simple as can be, elemental 1928 lifeboat. I really don't want to hide this or make it into anything else. I could potentially be happy with it as an completely open boat. The only reason I am considering compartments is safety, I am in a muddle if this is clearly more dangerous for myself and my family. If I can add unsinkable-ability for my family I feel I should. If I can add a berth so much the better. These reasons are why I envisioned sealing the forward 1/3 into a watertight berth with something similar aft enclosing tank-age and open in the middle with the mast. These fore and aft compartments I see as having a normal deck plus bulwarks preserving the lines. I don't envision any raised fore-decks or superstructure for aesthetic reasons. I want to keep the very graceful canoe lines it has. I don't have a current desire for a cabin but any design I build should be able to be built up in the future if so desired without undoing the open boat timbers. It may be possible the low shear is adequate under sail depending on how stiff she is but it is hard to guess. I have some ideas for the shear in the following.

    Before I started this post I envisioned mostly steel work, decks, bulkheads, bulwarks, mast shoe plate, but due to the thinness of the gauge and the age of the steel I have started to think about wood. My skills are I built by myself a Westsail 28 from a bare hull and deck into a fine little yacht capable of the partial circumnavigation I undertook. In metal terms I can weld, cut and braze but only have a ac stick welder. MIG is not in the picture.

    I have begun to abandon the steel work idea as the gauge is so light (1/16” perhaps)and old I fear blowing through or stressing and cracking it even if brazing. Brazing was my best hope but I still think it will put the hull at risk. Here is my idea using wood instead. I have a lot of 4" x 1/2" clear cedar, probably red. I found I could bend it to the shear fore and aft without breaking it. The vertical change in the shear was negligible to my surprise it remained parallel. My idea is to capture the top edge of the hull plate between cold-moulded (epoxy or other glue) layers of the ½ cedar. The lower 1/1/2 inch of the 4 inch cedar would clamp the top edge of the plate. Totally thickness of the cold-mould would be 1 ½ to 2 inches with the thin hull plate sandwiched between the layers at some point. A steel or hardwood rubrail would then be through-fastened through all (rubrail, cold-mould cedar and hull plate). This would yield a very strong, light (cedar) member to retain the shear form and form a base to build on. After adding a cap to the cold-mould shear I would have just raised the shear by at least 4 inches ( 3 plus cap) to get a lowest shear height of 14 plus 4 = 18 minimum. I think the old waterline was off because the cabin was heavy so it might float at 20 in freeboard as a guess. I would now have a stout shear structure, preservation of lines, and something to build from all with no steelwork. I could always add a bulwark board on top too. How Im I doing on shear height now?

    From here my open-boat vision includes a double-sawn cedar cross beam. My local lumber yard has some nice 2 by red cedar boards. These would tie into the shear cold-mould. A few more cedar timbers and keel cover plate of some material would complete the open boat plan, very elemental. After bolting the keel back and getting the engine and reverse gear back in I could go for a motor launch test. If that looks good on I could rig and she how she sails. If that looks good I would come back to watertight compartments feasibility and or a possible cabin.

    In any case my cedar beams would already be in the right place hopefully. Bulkheads of some material could tie to these cedar cross beams. The hull has the original inside seat board mounts I could put back to work aft with cedar cross-hull seat boards. The hull also has riveted floor board plank retainer loops that can be put to use.

    The first conversion fore-deck had a very pretty curved foredeck and I have the beams for a pattern.

    So that is my best thinking to date. Please tear it apart! If you think I should be welding or brazing to the hull instead please. I can weld well enough on heavier stock but fear the old dirty thin stuff.

    If I get to watertight bulkheads the question will be how to join to the hull.

    I want to get this in then I will get to pics and measurements. I appreciate your feed back very much, this is not such an easy project for me. I believe the hull is worth it and the historical aspects and beauty of the lines compared to other lifeboats inspire me.
     
  7. newindustar
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    newindustar Junior Member

    I uploaded attachments, not sure how to get them in here though.

    The original plaque on the bow claims:
    20 person
    204 cubic foot capacity
    2.58 foot depth
    22 foot long
    6 foot beam

    The bolt on keel from the first sail conversion is 12 feet long, 22 inched high, and 2 inches thick. Supposedly it weight 1500 lbs, I don't know if this is accurate. Added to the design depth (draft) the sailboat draft is about 4.4 feet.
     
    Last edited: Jul 24, 2010
  8. welder/fitter
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    welder/fitter Senior Member

    "newindustar",
    First, can you give us a name to call you by? It'd be easier than saying "Hey you", or words to that effect.

    I re-read your post after posting and giving some thought to Tad Roberts's comments, as well. If I had thought more about what you had written, I would have realized that you are someone who seems to know what you're looking at. My bad.

    I'd like to help you, to the extent that I can, but also believe that there are those more qualified &, I suggest the following: With pictures & some measurements, we can all get a better handle on what we are looking at. Perhaps, a free-hand sketch, as well, of what you think the "end product" would/should/could be. You've probably heard of cladding & we do some of that out here (Vancouver) on some of the beautiful old boats & ships, so that is always a consideration. Yes, wood to raise your freeboard might be another route, we'll have to look at the photos & "kick" that idea around. With the measurements & photos I will try to re-create the lines with Rhino and maybe someone like Tad could correct/point out any of my errors. If a student of design who is more qualified than I wishes to take on the project, I will gladly step aside without feeling my ego bruised, as I know that I still have a long way to go.

    I tried to send you a similar message, but I think you need 10(?) posts before that is possible.

    Mike

    Edit: Whoops! posted when you did! lol I'll have a look, now
     
    Last edited: Jul 24, 2010
  9. welder/fitter
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    welder/fitter Senior Member

    Can't see them. Did you go to advance search & attach? I put some on a post last week & have already forgotten, once again, how to do it. mess around with it & you'll figure it out.
     
  10. gonzo
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    gonzo Senior Member

    A 22 foot double ender will hardly have sitting room. If you add freeboard, it will be top heavy. The boat is what it is. If you want more room, this boat is a bad choice.
     
  11. newindustar
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    newindustar Junior Member

    Excuse me, My name is Hudson, Hudson Porter. Gl;ad to meet you.

    If you copy and paste the links into another browser window browser you can see them that way. I tested it. They are already uploaded but I did not see how to make them appear in the body. My cold-moulded shear is essentially what they did (sandwitching the top plate between wood but they had the benefit of long steam bent or doublesawn or green stock which I don't have. I actually don't know how they got their wood on, I'd be curious to know.

    I agree the hull is what it is and it was never deep enough for a comfy sitting cabin. This is why I want to make it an open boat, even if the open part is only the middle 1/3 of the boat, fore and aft being watertight compartments or just berth and tankage respectively. If you read closely I am not talking about doing raised decks per se, just a slight sheer (shear) increase. Four inches would be subtle yet significant, I am hoping to find that magic compromise. Having it an open boat in the middle would make it very comfortable under the boom i think.

    I will try to sketch.
     
  12. newindustar
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    newindustar Junior Member

    Steel still an option

    I lay awake thinking last night. I translated my concept of sandwiching the top plate edge in cold-mold cedar to steel, say two layers of 1/8" yielding a 5/16 thick unitized gunwale, rubrail, and bulwark. In steel the height could be anything we decide would yield the ideal freeboard. I would not have to weld to the hull but would use mechanical fasteners along with perhaps a metal bond epoxy. Now I would have something to weld to with some substance! I could weld decks and cross-members to the inside of this new top plate if I proceed to watertight compartments in the future I can weld in bulkheads in a truly watertight fashion. Steel would free me to add 8 inches to my freeboard yielding a least freeboard of 24" if that was deemed ideal.

    Yes the question of top hamper needs to be considered but taking into account I am talking flush decks I have a gut feel she could take perhaps up to 8 inches of additional freeboard. Also the design cannot be considered properly with out taking that 12 foot long keel into account.

    So I come back to my original question of what could be the ideal freeboard on this hull now you have most specs, and some pictures (just click on the links and the pictures come right up) and design philosophy.

    I could actually handle the new steel plate addition well within my skills and equipment now that I realize I would not have to weld to to the original top plate. I could use help with the scantlings for the steel once ideal freeboard is determines.

    I could order say 8 inch strips sheared from 1/8" 12 foot plate, weld them end-to-end to yield 24 foot strips and get to work.

    One issue with my 4 inch cedar is they are only 6 foot long needing a lot of overlaps and end joints and glue, could be tricky and messy and would not add much to the freeboard.
    I don't think it feasible or affordable to find wide thin long clear wood stock to cold-mold with. If my existing cedar won't get the job done I think I need to go steel, Galvanized of course.

    I know it looks pretty ugly in the pics as I just barely got the cabin off. However I started using paint stripper inside the hull and am finding galvanized plate in so far very good shape with strong looking rivet laps.
     
  13. welder/fitter
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    welder/fitter Senior Member

    Sorry, Hudson, when I click on them, or try to open them in another window, I get a note saying if valid attachment please contact administrator, or some such message. I've tried it signed in, not signed in, in separate window, etc. . Anyone else able to view photos?
    Mike


    "Invalid Attachment specified. If you followed a valid link, please notify the administrator"
     
    Last edited: Jul 25, 2010
  14. Pauls
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    Pauls Junior Member

    I'd suggest that you consider riveting to attach your freeboard extensions, etc to the hull. Riveting is easy to do and easy to learn if you're new to it. It is very well suited to thin metal structures like your hull. You won't have any issues with problems welding to the thin steel, and it can be very sound structurally.

    Paul
     

  15. Jeff
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    Jeff Moderator

    When you upload attachments, make sure you close the attachment upload window and finish submitting the post in the main window.
    I.E.
    1.) Click Go Advanced, Edit, or big blue Post Reply button
    2.) Click Manage Attachments
    3.) Select the attachments
    4.) Click Upload
    5.) Click Close Window on the attachment window
    6.) Click Submit Reply (or Submit Post) in main window
    If you don't submit the post in the main window after selecting the attachments, the attachments from the small window won't get permanently added or associated with the post. Sorry this isn't clearer -- once you do it once it's not an issue, but it's not the most user friendly aspect of our site for new members.
     
    1 person likes this.
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